Robotic pool cleaners have existed in the market place for some time. Numerous prior art exists disclosing a wide variety of different types of automatic swimming pool cleaners, most of which utilize an external power source provided at the surface of the pool for providing power to the cleaner. For example, some prior art cleaners require plugging the cleaner into an outdoor electrical socket, using a floating battery connected by a length of cable, or using a supply of pressurized water from a pump. In all of these different types of robotic pool cleaners, the cables or cords, which are tethered to the cleaner, used to supply power to the cleaner can get tangled and can impede the functionality of the robot as it moves through the pool. In addition, most automatic pool cleaners are substantially heavier than water thereby requiring the user to lift a substantial weight to the surface of the pool usually by pulling on the supply lines or, in some cases, utilizing a hook or winch to lift the cleaner to the water surface.
In addition, there are some cordless battery operated robotic pool cleaning devices. See for example, U.S. Pat. No. 6,294,084 to Henkin as well as Applicant's U.S. Pat. No. 9,399,877. These devices include a complicated propulsion system involving gears, belts, pulleys and other mechanisms for rotating and driving wheels associated with such devices along the floor and wall surfaces, hereinafter referred to as wall surfaces, of the pool to be cleaned and further include brush assemblies, a plurality of valves, inlet and outlet ports, hoses, filter bags accessible only from the bottom of the unit, and in the case of the cleaner disclosed in U.S. Pat. No. 6,294,084 to Henkin, a level control subsystem that includes a closed fluid chamber containing an airbag used to modify the buoyancy of the apparatus for submerging and raising the cleaner in the water. All of these devices are extremely complicated, expensive and include numerous parts that can fail, need repair, or simply cannot be repaired. Other prior art units are heavy and difficult to remove from the pool; some units must be manually retrieved from the bottom of the pool; some units employ complicated and expensive valve or ballast assemblies; and some units utilize filter bags which are difficult to clean and maintain.
Still further, U.S. Pat. No. 6,412,133 to Erlich discloses a tethered swimming pool cleaner that uses a single directionally controlled water jet propulsion system that utilizes a complicated diverter or deflector system for varying and changing the directional discharge of the water jets for controlling the direction of travel of the cleaner. Here, orientation of the discharged water jet is varied by the diverter system to provide a downward component or force vector, lateral components, or a combination of both to complement the translational force. During the change from one water jet discharge position to another water jet discharge position, the cleaner must be stabilized by interrupting the flow of water from the discharge conduit, such as by interrupting power to the pump motor or discharging water from one or more orifices. This is a complicated and inefficient method for providing water jet propulsion to the cleaner.
In view of the foregoing, it is therefore desirable to provide a cordless robotic pool cleaning apparatus which is easy and simple to operate and maintain, does not use a wheel driven system for propulsion, is lightweight and easy to carry, utilizes a buoyant design which allows the unit to return to the pool surface when the cleaning cycle is completed thereby negating the need for a user to perform manual labor in retrieving the machine from the bottom of the pool, and which does not use a complicated valve or diverter system for any of its operations. These and other features and advantages of the present unit will become apparent to those skilled in the art after reading the present disclosure.